1. Notes on Chapter 14.1
What is an Animal?

2. Multicellular Makeup Made of eukaryotic cells
Lack cell walls; only surrounded by cell membranes
Multicellular – made of many cells that work together

3. Organization in Animals
Specific cells specialize to perform specific functions
Same cells that work together form tissues
Tissues that work together to perform a specific function form organs
A group of organs that work together to perform a specific function make up an organ system

4. Body Plans
Symmetry
Asymmetrical – body not organized around a center Ex. Sponge
Radial – body is organized around a center, like spokes on a wheel Ex. Starfish
Bilateral – two sides of body mirror each other Ex. Tortoise
Cephalization – central head region with sense organs concentrated
Coelom – body cavity that surrounds and protects many organs

6. Getting Energy
Animals cannot make own food – consume other organisms (consumer/ heterotroph)
Many different types of food eaten by animals

7. Reproduction Some animals may reproduce asexually
Ex. Budding in hydras – part of an organism develops into a new organism
Ex. Fragmentation in sea stars – parts of an organism break off and develop into new individuals
Most animals reproduce sexually – sperm + egg, fertilization

8. Development Fertilized egg divides into many cells to form an embryo
As multicellular organism develops, cells become specialized during differentiation – process by which cells that will perform different functions develop different structures

9. Movement
Nearly all animals move to search for food, shelter, and/or mates
Some only move during larval stage (ex. Sponge larva)
Muscle cells contract and relax to move organisms

10. Maintaining Body Temperature
Endotherms – maintain body temperatures using energy released through chemical reactions
Ex. Birds, mammals
Ectotherms – rely on environment to maintain body temperature; may have developed behaviors to control tems.
Ex. lizards